As PPs have said there are quite a few different types of family/relative/known person carers. Really depends on whether the DC has LAC status (Local Authority hold PR and usually have to provide funding) depending on the way things happened if its voluntarily/Court order
I think if DC is LAC it would likely be Connected Persons (Funding from LA), if LA are looking for a more permanent placement they will likely push to change it to Special Guardianship Order or a Child Arrangement Order if there is a possible family member as these are cheaper.
If DC isn't LAC then would likely be private fostering/kinship (No Funding from LA), again if LA are looking for a more permanent placement they will likely push for Special Guardianship Order or Child Arrangement Order - a SGO can provide financial support (Not sure about a CAO) but only if pre-agreed before order is made, not paid until order is made and is means tested (Just my experience)
I went through the long, intrusive assessments (Think there were two, initial viability assessment then much more indepth SGO assessment) with my two (Non-LAC) nephews, everyone thought I was crazy as I was mid/late 20's, no DC & male - best decision I've ever made though but it was tough dealing with the long period (mine was 11months as it was a big case and large sibling group) of assessments/court/meetings, but thankfully the SWs dropped us fast, on paper its 3 months but got 1 visit a month after SGO and that was it. I had no training, they did send me on a 12 week parenting course as a SW mentioned it on my viability assessment so they had to but apparently I didn't need it and actually missed the last 2 weeks due to court and sw meetings.
If you think you can help I would contact Childrens Services and put yourself forward, then you might get a chance to talk about what has happened, what if anything is needed. I remember a SW telling me they needed the actual person to put themselves forward and couldn't take recommendations from others - probably to avoid the LA theoretically "placing" DC and then having to provide financial support at the beginning.